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[Federal Register Volume 89, Number 246 (Monday, December 23, 2024)]
[Notices]
[Pages 104535-104536]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-30508]

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ENVIRONMENTAL PROTECTION AGENCY

[EPA-HQ-OAR-2024-0446; FRL-12501-01-OAR]

Notice of Approval for Other Use of Phosphogypsum

AGENCY: Office of Air and Radiation, Environmental Protection Agency 
(EPA).

ACTION: Notice.

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SUMMARY: The Environmental Protection Agency (the EPA or the Agency) 
has approved, subject to certain conditions, the request for a ``Small-
scale Road Pilot Project on Private Land in Florida'' submitted by 
Mosaic Fertilizer, LLC in March 2022, and updated by the ``Revised 
Request for Approval of Use of Phosphogypsum in Small-scale Pilot 
Project'', submitted in August 2023. The Agency's review found that 
Mosaic's request is complete per the requirements of EPA's National 
Emissions Standards for Hazardous Air Pollutants under the Clean Air 
Act, and that the potential radiological risks from conducting the 
pilot project meet the regulatory requirement that the project is at 
least as protective of public health as maintaining the phosphogypsum 
in a stack. On October 9, 2024, the EPA issued a pending approval of 
the request and solicited public comments on the pending approval. 
While EPA received comments raising questions about the project, no 
comments were received which led EPA to change the results of its risk 
analyses for this proposed pilot project. This approval is only for the 
proposed pilot project, and EPA has placed conditions on the approval 
to make sure that the project remains within the scope of the 
application.

DATES: This decision is effective immediately.

FOR FURTHER INFORMATION CONTACT: Jonathan Walsh, Radiation Protection 
Division, Office of Radiation and Indoor Air, Mail Code 6608T, 
Environmental Protection Agency, 1200 Pennsylvania Avenue NW, 
Washington, DC 20460; 202-343-9238; [email protected].

SUPPLEMENTARY INFORMATION:

I. Background

    Phosphogypsum is the waste byproduct of wet acid phosphorous 
production. It contains elevated concentrations of the radionuclide 
radium, which decays to form radon gas. The EPA's regulations under the 
Clean Air Act at 40 CFR part 61, subpart R (hereafter ``Subpart R'') 
require that phosphogypsum must be disposed of in engineered piles, 
called stacks, to limit public exposure to its radioactive components. 
Subpart R allows the removal of phosphogypsum from stacks for outdoor 
agricultural purposes and indoor research and development, subject to 
conditions and restrictions. Any other use of phosphogypsum requires 
prior approval from the EPA. The EPA may approve a request for a 
specific use of phosphogypsum if it determines that the proposed use is 
at least as protective of public health as placement of phosphogypsum 
in a stack. The processes for requesting such an approval are described 
in 40 CFR 61.206.
    Mosaic Fertilizer, LLC submitted a request for a Small-scale Road 
Pilot Project on Private Land in Florida in March 2022, and submitted a 
Revised Request for Approval of Use of Phosphogypsum in Small-scale 
Pilot Project in August 2023. Mosaic has proposed to construct a small-
scale pilot project at its New Wales facility in Polk County, Florida. 
Mosaic's plan is to construct four sections of test road having varying 
mixtures of phosphogypsum (PG) in the road base ``to demonstrate the 
range of PG road construction designs that meet the Florida Standard 
Specifications for Road and Bridge construction'' (Request for Approval 
of Additional Uses of Phosphogypsum Pursuant to 40 CFR 61.206, Small-
scale Road Pilot Project on Private Land in Florida). The pilot project 
will be constructed in the place of an existing facility road near the 
phosphogypsum stack, and the study will be conducted in conjunction 
with researchers from the University of Florida.
    The EPA performed a complete review of Mosaic's request, documented 
in ``Review of the Small-scale Road Pilot Project on Private Land in 
Florida Submitted by Mosaic Fertilizer, LLC'' (www.regulations.gov, 
Docket ID No. EPA-HQ-OAR-2024-0446). The Agency's review found that 
Mosaic's request is complete per the requirements of 40 CFR 61.206(b). 
Further, the review found that Mosaic's risk assessment is technically 
acceptable, and that the potential radiological risks from the proposed

[[Page 104536]]

project meet the regulatory requirements of 40 CFR 61.206(c); that is, 
the project is at least as protective of public health as maintaining 
the phosphogypsum in a stack. Therefore, the Agency issued an approval 
of the small-scale pilot project per 40 CFR 61.206, subject to terms 
and conditions which limit the project to the scope of the application. 
The terms and conditions are included in the approval letter to Mosaic, 
which is available in the public docket and on the EPA website, https://www.epa.gov/radiation/phosphogypsum. Approval by the Agency is 
specific to the pilot project as described in the Mosaic request and 
indicates only that this project meets the approval requirements of 
Subpart R.

II. Public Comments and Responses

    The EPA's decision to approve or deny a request for other use under 
40 CFR 61.206 is not a rulemaking. In December 2005, the EPA issued a 
guidance document, ``Applying to EPA for Approval of Other Uses of 
Phosphogypsum: Preparing and Submitting a Complete Petition Under 40 
CFR 61.206, A Workbook'' (December 2005). Although this guidance is not 
binding, the EPA sought public comment on this pending approval using 
the procedure described in Section 2.4 of the Workbook. As outlined in 
the Workbook, the EPA published a notice of availability of this 
pending approval in the Federal Register on October 9, 2024, and opened 
a 30-day comment period, which was extended in response to public 
requests for an additional 15 days to close on November 23, 2024. 
Physical copies of the Mosaic request and the EPA's technical 
evaluation were placed for public review in the Mulberry Public 
Library, 905 NE 5th Street, Mulberry, FL 33860. The EPA also placed 
notices of public availability in local newspapers.
    The EPA has reviewed all comments received for their relevance to 
the pending approval.
    Many comments requested an extension of the 30-day comment period. 
The EPA extended the comment period in response to these requests.
    The majority of comments were generally opposed to the use of 
phosphogypsum in public roads, and critical of the current state of 
phosphogypsum management; these comments were determined to be outside 
the scope of this action, which is specific to the small-scale pilot 
project as it is described in Mosaic's request. The EPA's approval 
applies only to the proposed pilot project and not any broader use. Any 
other use would require a separate application, risk assessment, and 
approval.
    Comments related to EPA's management of phosphogypsum and its non-
radiological contaminants under the Resource Conservation and Recovery 
Act and other statutes similarly fell outside the scope of the current 
decision. EPA has documented other regulatory issues in its supporting 
documents, but EPA's decision is only a determination of the 
permissibility of the project under the Clean Air Act National 
Emissions Standards for Hazardous Air Pollutants for Radionuclides. It 
does not imply any other regulatory approval or determinations of 
compliance. These must be obtained or made separately from this 
decision.
    Some commenters indicated that EPA established a legal ban on the 
use of phosphogypsum in road construction by considering but not 
issuing a categorical approval in 1992. Road use is not prohibited by 
the regulation as amended in 1992 and is eligible to be considered as 
an ``other use.''
    Commenters were critical of many aspects of the risk assessment. 
Commenters questioned the EPA's overall ability to perform radiological 
risk assessment, use of fatal radiogenic cancers as a health endpoint, 
selection of dose and risk coefficients, selection of models, and 
selection of exposure scenarios and whether current risk data was used. 
Specifically, several commenters believed that greater emphasis should 
be placed on the consideration of a future resident at the site of the 
pilot project. These comments represent disagreements with decisions 
that EPA has made in its evaluation of potential risks associated with 
the proposed pilot project, rather than new information that the Agency 
has not previously considered. After reviewing the comments, the EPA 
continues to believe that the risk assessments associated with this 
pilot project are consistent with current radiological risk assessment 
methodologies and precedent, and sufficient to evaluate the project per 
the requirements of 40 CFR 61.206. Results from multiple modeling 
efforts indicate that risks due to the proposed pilot project are low. 
EPA believes that for this existing site, it is most appropriate to 
consider the potential risk to site workers and the nearest residents 
to the site when determining whether the pilot project is as protective 
as leaving the phosphogypsum in the stack. No comments raised topics 
which EPA did not consider in its technical evaluation or lead to a 
concern for human health or environmental impacts not previously 
considered.
    The Agency's response to comments document is available in the 
public docket \1\ and on the EPA phosphogypsum website,\2\ together 
with electronic copies of the application, the EPA's review, and 
relevant background materials.
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    \1\ https://www.regulations.gov, Docket ID No. EPA-HQ-OAR-2024-
0446.
    \2\ https://www.epa.gov/radiation/phosphogypsum#aaup.

Joseph Goffman,
Assistant Administrator, Office of Air and Radiation.
[FR Doc. 2024-30508 Filed 12-20-24; 8:45 am]
BILLING CODE 6560-50-P
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